I think you are correct in what you are worrying about. Bolts will likely just stretch a little unless you really go ape. But a motor's internal threads are a lot harder to fix.
I'll make a pitch for ZERO loctite regardless of the strength used. A properly applied, correct torque spec is almost always the solution to a bolt backing off on a bike. I've seen plenty of issues with even blue loctite on mission critical parts.
If you MUST use a threadlocker, consider Vibra Tite gel. Also blue. VT is a vibration-resistance product with roots in aviation. It never truly dries. It just goops up the threads sufficiently so they don't back off. I learned about it participating in shooting sports, where the old hands use it on extremely expensive - and delicate - optics that are subject to repeated, severe recoil impact.
Another trick preferable to thread locker: Use registration marks. The first pic shows a big fat sharpie covering the two rings plus the bottom bracket of a BBSHD install. Its meant to be seen from a standing glance down so I made it obvious. In the second picture I used a thin red oil pencil from Amazon on much smaller parts (the pencil'd rings show if the tube is shifting back/forth).
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Do marks like this and all you have to do is glance at them to see if they can be left alone.
